In the News: 10/03
Why We Feel Pain Differently
Brain imaging has confirmed that some people really are more sensitive to pain than others. Researchers at Wake Forest University’s Baptist Medical Center placed a heat simulator on the legs of 17 subjects. Their brains were then scanned by MRI to assess brain activity. Participants who reported that the heat stimulus was extremely painful showed pronounced activity in certain regions of the brain; others, who said that the stimulus was only mildly painful, exhibited only minimal activity in the same areas of the brain.
People reporting high levels of pain showed increased activity in the primary somatosensory cortex, which contributes to the perception of pain intensity and where it is located, and the anterior cingulate cortex, which processes the unpleasant feeling caused by pain. However, there was little difference between the study’s subjects in activation of the thalamus, which is involved in transmitting pain signals from the spinal cord to the brain.
Said investigator Robert Coghill, Ph.D., in June’s Proceedings of the National Academy of Sciences, “The difference between cortical and thalamic patterns of activation may explain pain differences between individuals. The finding raises the possibility that incoming painful information is processed by the spinal cord in a similar manner. But once the brain gets involved, the experience becomes very different from one individual to the next.”
Goghill said that, until now, there has been no objective evidence that individual differences in pain sensitivity are real. “One of the most difficult aspects of treating pain,” he added, “has been having confidence in the accuracy of patients’ self-reports of pain.” As they prescribe pain medications, Coghill concluded, doctors can trust what their patients tell them about the intensity of their pain.
RA Sufferers Twice As Likely To Have Heart Attacks
Researchers at Harvard Medical School have found that women with rheumatoid arthritis were twice as likely to suffer heart attacks as women without the disorder. And those who had the condition for more than 10 years had triple the risk. Although the Arthritis Foundation-funded research examined only data on women (based on a study of 114 nurses that began in 1976), the results, says Dr. Daniel Solomon, one of the study’s authors, likely also apply to men with RA. Inflammation, which results when the body’s immune system invades healthy tissue lining the joints, is what causes rheumatoid arthritis. The same inflammatory process, says Dr. Solomon, damages the blood vessels as well—and inflammation of blood vessels plays a key role in atherosclerosis (hardening of the arteries). The steps taken to prevent heart disease are the same as those recommended for the management of arthritis: Exercise regularly, watch your diet, maintain a healthy weight, and get plenty of sleep.
Arthritis More Common In Smokers, Divorced
Divorced or separated people are 30 percent more likely than married people to have arthritis, while people who smoke every day are 60 percent more likely to be at risk of the disease. This is the conclusion of a study conducted at the Centers for Disease Control and Prevention in Atlanta, Ga., which surveyed more than 54,000 people in 15 states and Puerto Rico. The study did not differentiate between osteoarthritis and rheumatoid arthritis, which led the study’s author, Dr. Charles Helmick, to conclude: “When you combine all types of arthritis, smoking seems to have an effect.” In terms of why arthritis may be associated with separation or divorce, Dr. Helmick ventured that severe types of arthritis might put stress on a marriage. Alternatively, he said, the stress of a marital breakup may also aggravate the beginning stages of arthritis.